Bearings and Seals Flashcards
- All bearings are designed to provide support to moving parts, keep parts in
alignment, increase friction and provide a replaceable wear surface.
a) true
b) false
false; Bearings are designed to decrease friction
- Axial loads may be offset by:
a) plain roller bearings.
b) straight splines.
c) helical splines.
d) needle bearings.
c) helical splines.
- Crush is a tenn used to describe the:
a) force on a preloaded bearing.
b) press force required to remove a bearing.
c) distortion of an anti-friction ball bearing.
d) radial pressure exerted on the bore.
d) radial pressure exerted on the bore.
- Choose the answer that does not describe an anti-friction bearing.
a) high contact area between moving parts
b) may be lubricated for life
c) higher cost and greater complexity
d) designed to absorb combination loads
a) high contact between moving parts.
- Plain roller bearings are designed to support radial loads only.
a) true
b) false
A. True
- Needle bearings are:
a) most often used where space is limited.
b) designed to absorb combination loads.
c) 10 times as long as their diameter.
d) actually taper roller bearings
a) most often used where space is limited.
- Choose the term that best describes static seals.
a) They do not move.
b) They seal a moving shaft.
c) They seal between non-moving parts.
d) They have one spring on the lip.
c) They seal between non-moving parts
- O-rings may be replaced with silicon if needed.
a) true
b) false
false; Silicone is only used as a sealant in place of a gasket
- Choose from the following the sentence that best describes gaskets.
a) Gaskets are used between moving surfaces.
b) Metallic gaskets are usually made of cork, rubber, plastic or a combination.
c) Non-metallic gaskets are usually of thin or heavy solid metal.
d) Metal gaskets can usually withstand higher pressures and temperatures.
d) Metal gaskets can usually withstand higher pressures and temperatures.
- Silicone may be used with cork or paper gaskets.
a) true
b) false
false; Do not use silicon with cork or paper gaskets as the gasket may slip out or
become too thick.
- Choose the term that best describes face seals.
a) Face seals tend to have a high leakage rate.
b) There is little or no wear on the moving shaft.
c) Face seals are unable to contain high pressure due to their design.
d) Face seals have threads cut across the face of a shaft or cover.
b) There is little or no wear on the moving shaft.
- Choose the answer that best relates to preload.
a) Preload is a clearance.
b) Preload cannot be placed on ball bearings.
c) Preload is hannful to bearings.
d) Preload is set by shims, spacers or a threaded ring.
d) Preload is set by shims, spacers or a threaded ring.
- Brinelling is:
a) flaking of the bearing.
b) indentations from shock loading.
c) a result of the lack of lubrication.
d) normal bearing wear.
b) indentations from shock loading.
- With regard to bearings, arcing is a term used to describe:
a) the path of one roller within a bearing as it rotates 90°
.
b) the movement of a shaft on the outer portion of a bearing.
c) marks on the bearing due to discharges of electricity within the bearing.
d) rollover of a hub when the bearing becomes loose.
c) marks on the bearing due to discharges of electricity within the bearing.
- List three (3) contributing factors that lead to abnormal bearing fatigue.
a)
b)
c)
Any three (3) of the following are correct.
a) Operating above the dynamic load rating.
b) Operating at speeds above the bearing rating.
c) Shock loads.
d) Vibrations.
e) Operating at extreme temperatures - above 150° C (300°F).
